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Any air compressor suggestions?

CherryK5

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I finally have on-board air! But no compressor, i just fill it up when its empty.

Any suggestions at all? i want something semi small that will fill a 5gal tank pretty easily. And the cheaper the better.
 
Hit the junk yard for a York AC compressor then contact muddytazz on here about some brackets he makes. This will be your best bet and cheaper than any electric pump that could never come close to the air supply that a York puts out.
 
Will this fit with factory brackets? Yes mine has a/c and yes I am a pussy. Try living with 110 degrees and 95% humidity and you would have a/c too.
 
Will this fit with factory brackets? Yes mine has a/c and yes I am a pussy. Try living with 110 degrees and 95% humidity and you would have a/c too.

I get funny looks from my buddies when i'm wheeling in the heat with the windows up and the AC blowing real cold. :D Guess that makes me a pussy as well, so be it then.
 
well we own a junkyard and have a ton of compressors off old busses and stuff. But I want an electric one to keep my gas mileage as high as possible. I don't want a full time belt driven compressor. And no yorks. We had one but can't find it. =/

how hard would it be to put an a/c clutch pulley on a compressor?
 
Umm..The York is an A/C compressor - so they came with clutches for the OEM installs. The trick is getting a pulley that's right for your setup.
 
Umm..The York is an A/C compressor - so they came with clutches for the OEM installs. The trick is getting a pulley that's right for your setup.

Yea I knew the york had one.

But the a/c clutch would be on a pressure switch and then a master switch of course.
 
But if you're doing on-board air you will obviously have a pressure switch. It's basically the same thing as the switch in your shop compressor - except you will wire it to the clutch instead of an electric motor.

EDIT: I'm confused. What A/C compressor didn't come with a clutch? And how is a clutched air pump "full time"? I can't even imagine running a mechanical compressor without a clutch. Where would you divert the air to once you reach pressure?
 
Yea I knew the york had one.

But the a/c clutch would be on a pressure switch and then a master switch of course.

The compressor is basically an idler pulley when the clutch is off, you shouldn't notice any difference in MPG.

And yes, a master on switch, and a pressure switch in series to the clutch.
 
I run my york with a master switch in the cab, then there is also a pressure switch. Now the pressure switch ONLY WORKS when the master is in the on position. Hit me up if you need more info.
 
Yep, I have a pressure switch and a master override to keep it turned off so there is no chance of a battery drain should I get an air leak and then the clutch kicked on.
 
Yep, I have a pressure switch and a master override to keep it turned off so there is no chance of a battery drain should I get an air leak and then the clutch kicked on.

Exactly, only turn the york on when needed (just like a stock a/c compressor).
 
But if you're doing on-board air you will obviously have a pressure switch. It's basically the same thing as the switch in your shop compressor - except you will wire it to the clutch instead of an electric motor.

EDIT: I'm confused. What A/C compressor didn't come with a clutch? And how is a clutched air pump "full time"? I can't even imagine running a mechanical compressor without a clutch. Where would you divert the air to once you reach pressure?

The compressors are for the air brakes and stop sign pneumatics. They run full time and then once they reach the pressure they need it opens a valve on top of the compressor so it doesn't compress.

They don't have clutches on them. Just a big 8 inch pulley.
 
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Most of the air compressors I used to see on our route trucks with air brakes, had the clutch.
However, if a compressor has an unloader setup, then you will not see much in the way of gas millage difference either.

Our big air compressors at the plant, one 25 horse, one 40 horse, and a 50, all had unloaders.
When the pressure switch tripped, it closed both the intake and exhaust valves.
That reduced the load on the motor to just friction loads in the crankcase and cylinders.

I'm sure that is how they do it on the big rigs. More reliable than a clutch.
 
Most of the air compressors I used to see on our route trucks with air brakes, had the clutch.
However, if a compressor has an unloader setup, then you will not see much in the way of gas millage difference either.

Our big air compressors at the plant, one 25 horse, one 40 horse, and a 50, all had unloaders.
When the pressure switch tripped, it closed both the intake and exhaust valves.
That reduced the load on the motor to just friction loads in the crankcase and cylinders.

I'm sure that is how they do it on the big rigs. More reliable than a clutch.

Good news for me! I guess i'll give it a try, and if im not liking it i'll just pull it back off. and go electric or york (if i find one)
 
Its a little counterintuitive. You would think closing both valves would cause the engine to use more power to drive the piston into a closed system. Which, it does, but you get that power back when the crank moves overcenter.
Then, that pressure pushes the piston back down transferring power back to the engine.

The only energy lost is friction and a tiny heat loss.
A clutch is better, of course, but on big rigs reliability is more important.

On our big air compressors, you did not want to start and stop the motor possibly several times per minute, so you just tripped the unloaders on top of the cylinder heads with air pressure and the valves remained closed.

The 50 had 4 big cylinders, and it could load and unload them separately.
It had multiple pressure switches, set about 10 pounds apart, and would only kick in one cylinder to start with after the first full cutoff.

If the pressure continued to drop after the first one kicked in, it would kick in another cylinder every 10 pounds until it reached enough capacity to handle whatever load it was seeing.

Saved a lot on electricity.
 
To use an unloader valve all you need is an air governor. Thats what the big rigs use. One line comes from the tank to the supply port. One line to the top port (cant remember the name now) that will also come from the tank. and one line will go from the governor del port to the unloader port on the compressor. Pressure can be adjusted by a spring inside the governor but most of those are set at 125 psi stock.
 
I used this unloader on my york setup...

http://www.grainger.com/Grainger/CDI-CONTROL-DEVICES-Load-Genie-Unloader-5A704?Pid=search

No second tubes needed, no controls, just put that inline after the outlet to the york, right before the pressure switch or whatever you have after your flexable outlet hose. It opens up with flow, and closes automatically when flow slows, exhaust the air behind the valve, and trapping the air in front of the valve.

Also, you can find a small pressure switch that is automatic from the lowrider guys, just choose your pressure. Look here, I used the 90 - 120 psi unit.

http://grunionfabrication.com/air-suspension-pressure-switches-c-22_394.html

They have some nice 3 gallon aluminum air tanks too, lightweight.

This stuff doesn't take up any room, and functions great. I also got the braided stainless outlet line from grainger, 400 degree, 20 something bucks.

Also, you can get all the fittings and DOT air line from the trucking places, air brake parts.
 
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